1. Field of the Invention
The present invention relates to aqueous polyurethane/urea dispersions and in particular to such dispersions where the polyurethane/urea contains alkoxysilane groups.
2. Description of Related Art
The production of linear or cross-linked aqueous polyurethane-urea dispersions is known as disclosed in U.S. Pat. Nos. 3,479,310; 4,066,591; 4,092,286; 4,108,814; 4,237,264; and 4,238,378 which describe linear polyurethane-ureas and U.S. Pat. Nos. 3,870,684, 4,203,883 and 4,408,008, which describe cross-linked polyurethane-ureas. The aqueous polyurethane-urea dispersions may be used for a wide range of commercial applications such as adhesives or coatings for various substrates including textile fabrics, plastic, wood, glass fibers and metals. Chemical resistance, abrasion resistance, toughness, tensile strength, elasticity and durability are among the many desirable properties of these coatings. In some cases these properties of coatings prepared from aqueous polyurethane-urea dispersions have equaled or even surpassed the performance levels of coatings obtained from solvent-based polyurethane lacquers.
Regardless of the property level which may be obtained for coatings prepared from commercial polyurethane-urea dispersions, there is a continuing need to improve such properties, in particular water resistance, solvent resistance, weather resistance and physical properties such as abrasion resistance. As commercial requirements become more demanding, there is a need in the art to provide adhesives and/or coatings with improved water resistance, solvent resistance, weather resistance, and abrasion resistance.